Dredging-machine.



No. 650,674 Patented May 29, I900.

E-GAEJEIERT &. I. M. HOFSTAD.

HfiEDGlNG MACHINE.

(Application filed Dec. 26, 1899.) (No Model.)

Pzrzns co, wonmumo, WASNINGTON, u. c.

rrtn STATES PATENT Fries,

FREDERIC EOAUBERT, OF NEW YORK, N. Y., AND ISAAC MYHRE HOFSTAD, OF SITKA, ALASKA TERRITORY.

DREDGlNG-MACHINE.

SPECIFICATION forming part Of Letters Patent-No. 650,674, dated may 29, 1900. Application filed December 26, 1899. Serial No. 741,522- (No modeL) To all whom, it may concern:

Be it known that we, FREDERIO EOAUBERT, residing at New York, (Brooklyn,) in the county of Kings and State of New York, and lsAAo MYHRE I-IoFsTAD, residing at Sitka, Alaska Territory, both citizens of the United States, have invented a new and useful Improvement in Dredging-Machines, of which the following is a specification.

Our invention relates to a dredging-machine adapted to lift from the bottom of a river or other more or less shallow body of Water sand or gravel containing precious metals, which material is thereafter treated by apparatus forming part of the same machine. l-Ieretofore it has been difficult both to reach this material and to treat the same successfully; and the object of our invention is to overcome this difficulty.

In carrying out our invention we provide a vessel of suitable form and means for fixing the location of the vessel or for drawing the same gradually forward. We preferably employ a long shaft extending over the forward part of the vessel, with theends of the shaft projecting beyond the sides of the vessel, and connected to and supported from the ends of this shaft at the opposite sides of the Vessel we employ a chain and bucket conveyer or similar dredging device that extends downward into the water and to the bottom of the body of water, and we employ means for rotating the shaft and means for weighting the lower ends of the endless chain and bucket conveyors, so that a pressure is exerted to compel the buckets to raise the sand or gravel, and adjacent to the delivery side of the said conveyers we employ sluiceways running longitudinally of the vessel and in which sluiceways the material brought up with the water in the buckets of the conveyors is treated for the separation of the precious metals from the waste material. a

We may place a sluiceway at each side of the vessel or the sluiceways may run over the surface of the vessel. In either case means are provided so that attendants can reach the sluiceways for their proper operation.

In the drawings, Figure 1 is a side elevation representing our improvement, and Fig. 2 is a plan of the same.

The vessel a may be of any ordinary suitable type, and it is to be provided with suitable power devices for propelling the same and operating the machinery connected therewith. We provide a shaft 19 in suitable bear ings b and which shaft extends transversely of the forward part of the vessel, with ends projecting beyond the sides of the vessel, and this shaft is to be driven by suitable power. The same may form part of the Winch of the vessel, usually located at the forward part thereof, or it may be operated by gearing from the said winch 9.

Connected to the respective ends of the shaft 19 is an endless chain and bucket conveyor c. This may be of any well-known and suitable form adapted to raise sand or gravel from the bottom of the body of water, and we prefer, in connection with this chain and bucket conveyer, to employ wheels 01 of sizes approximately agreeing with the wheels 0 upon the ends of the shaft 17 and over which Wheels the chain and bucket conveyor passes, These wheels 01, received at the lower end of the endless conveyer, keep the parts in their proper relation, so that the conveyer turns around the wheels and the wheels form weights to keep the conveyers taut and to compel the buckets thereof to do their work in digging into the sand or gravel, and in connection with these wheels 01 we prefer to employ shafts d,extending vertically toward the shaft b and passing through one or more guides 6 upon the sides of the vessel, so as to prevent a forward and backward swinging movement of the conveyers and their wheels d. These parts also move with any vertical movement of the vessel. I

We employ sluiceways f f adjacent to the delivery side of the conveyors, so that the contents of the buckets as the same pass over the wheels 0' are delivered into the said sluiceways, the water and gravel passing together into the sluiceways with whatever pre cious metal may be in the sand or gravel, and these sluiceways are inclined, so that the said materials pass down the-sluiceways and the precious metal is removed from the gravel by well-known means, and the refuse materials with the water pass away at the ends of the sluiceways.

To have shown in the drawings a sluiceway at each side of the vessel and a eonveyer at each side, the sluieeways being secured upon the outer surface of the vessel; but these sluiceways may pass over the vessel and longitudinally of the same by placing the chain and bucket conveyers farther forward, so that there will be less distance between the respective eonveyerscand a shorter shaft employed.

The construction or operation of the sluiceways forms no essential part of our present invention, as they maybe of any well-known form, and we have shown by dotted lines, Fig. 1, a power device adapted to operate the winch and bucket conveyers.

\Ve claim as our invention 1. The combination with the vessel and the power mechanism thereof, of a shaft extending transversely across the forward part of the vessel and suitable bearings therefor and means for rotating the same, the said ends of the shaft projecting beyond the sides of the vessel, wheels mounted upon the respective ends of the shaft and bucket conveyers around the said wheels and extending vertically down to below the bottom of the vessel, and weight- Wheels made heavy and received in the lowermost loops of the bucket conveyers to insure the digging action of the buckets, substantially as set forth.

2. The combination with the vessel and the power mechanism thereof, of a shaft extending transversely across the forward part of the vessel and suitable bearings therefor, and means for rotating the same, the said ends of the shafts projecting beyond the sides of the vessel, wheels mounted upon the respective ends of the shaft and bucket conveyers around the said wheels and. extending vertically down to below the bottom of the vessel, wheels acting as weights at the lower ends of said eonveyers, and around which the same turn, axles to said weight-wheels and rods placed vertically and guides therefor upon the sides of the vessel, and sluiceways running longitudinally of the vessel and located adjacent to the delivery side of the said bucket conveyers for receiving the material elevated thereby, substantially as set forth.

3. The combination with the vessel, the winch at the forward part of the same and the power mechanism for operating the winch, of a shaft extending transversely across the forward part of the vessel and suitable bearings therefor, and means for rotating the same by the winch, the said ends of the shafts projecting beyond the sides of the vessel, wheels mounted upon the respective ends of the shaft and bucket conveyers around the said wheels and extending vertically down to below the bottom of the vessel, wheels acting as weights at the lower ends of said conveyers, and around which the same turn, axles to said weight-wheels and rods placed Vertically and guides therefor upon the sides of the vessel, and sluiceways running longitudinally of the vessel and located adjacent to the delivery side of the said bucket eonveyers for receiving the material elevated thereby, substantially as set forth.

Signed by us this 18th day of December, 1899.

F. ECAUBERT. I. MYHRE IIOFS'IAD.

\Vitnesses:

GEo. T. PINCKNEY, S. T. HAVILAND. 

